i had my tranny rebuilt about six months ago and recently my torque converter has not been locking. at higway speeds it will go straight to overdrive without tc lockup. and when going about thirty five mph threw town with the od swith on it will not lock up either any ideas? thanks

 

if anyone knows anything about this could ya please chime in thanks.

 

I would take it to a transmission shop. Could be electrical or a bad seal in the trans.

Luke